The present invention relates generally to fluid flow in restricted areas and specifically to removing, reducing or preventing the build-up of paraffin, scale and salt encrustation at the fluid-structure interface as well as preventing emulsion problems.
The transfer of fluids through conduits or pipes causes numerous problems. One such problem is the adhesion of undesirable materials to the interior surface of the conduit. The problem of unwanted material adhering to the interior surface of a conduit transferring a fluid is critical because the inside diameter of the conduit decreases to restrict and can eventually prohibit flow therethrough. The phenomena of reducing flow in conduits is present at all stages of the transfer of petroleum products, i.e., removal from the earth formation to utilization by the end user.
Of primary concern, due to the extremely hostile environment, is the removal of the raw petroleum products from the earth formations. The tubing, pumps, and other equipment used downhole when petroleum products are being extracted from the earth formation are extremely susceptible to the adhesion of undesirable material on their surface. The adhesion problem is exaggerated in oil wells due to the extremely harsh physical and chemical characteristics of the environment in which the equipment is placed. The materials of primary concern are paraffin, scale, salt encrustation, and emulsions.
Paraffin accumulation on the surface of a conduit carrying petroleum products is of critical importance. The build-up of paraffin on surfaces has typically been prevented or removed by heating the surface or by scraping the surface. Typically, the conduit surface is heated by the injection of a hot fluid in the vicinity of the conduit and is scraped by the insertion of a wire-scraping device into the conduit. It has been found to be extremely expensive to utilize thermal or mechanical techniques to prohibit or remove paraffin build-up on the interior surfaces of a conduit carrying petroleum products. Thermal methods of preventing the formation of paraffin build-up require special expensive equipment and additional manpower. Most significantly thermal methods are quite expensive due to the lost production time incurred. Mechanical techniques for controlling and removing paraffin are cumbersome and expensive. Both direct costs and lost production time contribute to the expense of mechanically removing or controlling paraffin in a conduit carrying petroleum products.
In the past, scale build-up has been removed by chemical and mechanical methods. Chemical methods require the use of extremely strong and reactive substances such as hydrochloric acid. The highly reactive substances are then required to be extracted from the primary fluid being transferred. Mechanical methods for controlling and removing scale build-up are not effective and tend to cause additional problems. Scale build-up is typically removed from the walls by a "chipping" process which is not effective, reduces production time and increases costs.
The encrustation of salt on the interior surfaces of conduits carrying petroleum products is also a major problem. Salt encrustation has typically been controlled or removed by chemical and mechanical methods. The chemical and mechanical methods for the removal of salt encrustation have similar problems as the chemical and mechanical methods for the removal of scale. However, salt encrustation can be removed by injecting fresh water, eliminating the concern for using strong, reactive substances such as hydrochloric acid.
Emulsions are an acute problem in the transfer of petroleum products through conduits. Emulsion problems are exacerbated when extracting petroleum products from earth formations due to the hostile environment which includes but is not limited to heat, pressure and pH. Oil wells provide a system having different liquids dispersed in an immiscible liquid. The different liquids tend to stabilize, reduce the flow rate and inhibit production. Attempts to remedy emulsion problems have usually been directed toward thermal treatment on the surface or chemical treatment on the surface and downhole. Thermal techniques are expensive and cumbersome since the technique requires special equipment, additional manpower and reduces production time. Also, chemical methods have been used to prevent emulsifier action in conduits carrying petroleum products. Generally, chemical methods are used to disassociate the components of the emulsified fluid. As with the problems of scale build-up and salt encrustation, chemical methods tend to cause many complications that are as difficult to remedy as the emulsion problem to be solved.
All of the prior methods for preventing the build-up of paraffin, scale and salt, as well as preventing the emulsion problems are costly. The extreme cost is compounded by the direct expense of implementing the thermal, chemical, and mechanical techniques as well as the indirect expense associated with lost production time.
There is thus a need for a fluid treatment apparatus and method which prevents or reduces emulsion problems and the build-up of paraffin, scale and salt in conduits carrying fluids, which does not obstruct or inhibit the flow of the fluid, which is readily implemented in conjunction with the conduit, and which is inexpensive.
It is, therefore, a feature of the present invention to provide a fluid treatment apparatus and method for preventing and reducing emulsion problems and the build-up of material on surfaces in contact with a fluid utilizing magnetohydrodynamic principles.
It is a more particular feature of the present invention to provide a fluid treatment apparatus and method for preventing and reducing emulsion problems and the build-up of material on surfaces in contact with a fluid, utilizing what may be magneto-chemical effects to create an environment produced by the application of magnetic fields to turbulent fluid that inhibits or reduces the undesirable flow characteristics.
Another feature of the present invention is to provide a fluid treatment apparatus for preventing and reducing emulsion problems and the build-up of material on surfaces in contact with a fluid having a self-contained energy cell and requiring no external source of power.
Yet another feature of the present invention is to provide a fluid treatment apparatus for preventing and reducing emulsion problems and the build-up of material on the surface of a conduit in contact with a fluid that is easy to install and when installed can be a permanent part of the conduit.
Still another feature of the present invention is to provide a fluid treatment apparatus for preventing and reducing emulsion problems and the build-up of material on surfaces in contact with a fluid which has no moveable parts.
Yet still another feature of the present invention is to provide a fluid treatment apparatus for preventing and reducing emulsion problems and the build-up of material on the interior surfaces of a conduit in contact with a fluid which requires no maintenance.
Yet still another feature of the present invention is to provide a fluid treatment apparatus for preventing and reducing emulsion problems and the build-up of material on the interior surfaces of a conduit in contact with a fluid which is highly durable and which utilizes standard sizes and configurations to be easily adapted to any standard size equipment.
Additional features and advantages of the invention will be set forth in part in the description which follows and in part will become apparent from the description, or may be learned by practice of the invention. The objects, features, and advantages of the invention may be realized and obtained by means of the instrumentalities, combinations, and steps particularly pointed out in the appended claims.